Fonda-bonardi



y 1959 G. FONDA-BONARDI 2,894,229

MICROWAVE COMPONENT MOUNT Filed. Oct. 28, 1954 FIG. 1. FIG.

/N V5 N TOP. 6/05 70 FONDA -B0/vA 20/ 7 #[5 A TYPE/V516.

Il/JQP/S, K756, Fosra? & map/5 U ed e en '0 2,8 p Mrcnowsvn commitment 1 Giusto Fonda-Bonardi, Pasadena, can, assigndr to De- Mornay-Bonardi, Inc., 'l'asadena, Califl, a corporation ofCalifornia Application October as, 1954, Serial No. 465,213 ,ZClairns. cl.sss,---9is This invention relates to structures for positioning microwave components in waveguides .for ultra high fre' quency electromagnetic energy, and in particular to waveguide mounts for crystal rectifiers bolometers, and the like. i

In the use of waveguides it is often desired to position a circuit component within the waveguide and to have one or more electrical connections to this component which are insulated from the waveguide. A typical example of such a component is the crystal rectifier which serves to convert ultra high frequency energy 'to a relatively lower frequency or to direct current. i

Accordingly it is an object of the invention to provide a new and improved microwave component mount for positioning acomponent within a length of waveguide that is simple to construct and operate, occupies a minimum of space, is light'in weight, strong and dependable inoperation. 13

A further object ofthe invention is to provide amicrowave component mount in 'whichtthe component may be reversed in the mount sonth at thedusulated connection may be made either positive or negative with respect to thewaveguidewall. p

Another object of the invention isto provide amicrowave componentmount in which themounting isreversible so that an external connectioiitothe component may be made from either of'two sides of the waveguide.

Stillanother object of the inventionis to provide a dummycrystal for coupling with amicr.owave component to adaptit for use in sucha mount.

The invention also comprises novel details of construction and novel combinations and arrangements of parts, which will more fully appear in the course of the following description. However, the drawings merely show and the description merely describes a preferred embodiment of the present invention as applied to a mount for a crystal rectifier, which is given by way of illustration or example only.

In the drawings:

Fig. 1 is a side elevation of an embodiment of the invention;

Fig. 2 is an end elevation of the embodiment of Fig. 1;

Fig. 3 is an enlarged sectional view along the line 3-3 of Fig. 2;

Fig. 4 is an exploded isometric view showing the assembly of a coaxial type crystal and a dummy crystal into a microwave component for mounting in the embodiment of Figs. 1-3; and

Fig. 5 is an isometric view showing a second type of microwave component.

Referring now to the drawings and in particular to Figs. 1, 2 and 3, the numeral 11 designates a length of hollow waveguide having a coupling flange 12 mounted to one end thereof for coupling the waveguide 11 to other microwave circuits not shown. The waveguide 11 may have various cross-sectional shapes, such as round, elliptical, ridged or square, and in the embodiment of the invention illustrated, waveguide of rectangular cross sec- Patented July 7, 1959 tion is utilized. Two opposed openings 13 are made in the wall of the waveguide and bosses 14 and 15 are mounted to the outer wall of the waveguide. Each boss has anopening 16, 17 extending through it and each is positioned respectively over one of the openings 13 so that the centers of all four openings 13, 13, 16, 17 are aligned.

The. end of the waveguide opposite the flange 12 is shown as sealed by a plug 18. However, the invention maybe practiced in conjunction with waveguides having flagge couplings or other types of terminations at both en 8.

A suitable electrical conductor termination 19 is mounted to the boss 14. It is preferred in the practice of the invention to use coaxial conductors for making the electrical connections to the mount and a BNC type coaxial cable socket assembly is shown in the embodiment illustrated in the drawings. This assembly includes a case 20 having an internally threaded portion 21 which is attached to an externally threaded portion 22 of the boss 14. A jack 23 is screwed into a support block 24. The jack andblock assembly is held in position in a seat 25 in the boss 14 by two insulator elements 26, 27. A re- 'cess 28 is provided in the end of the block 24 opposite the jack 23. This recess 28 is of a size and shape suitable to support one end of a microwave circuit component 29.

One example of such a microwave component is shown in greater detail in Fig. 4. A coaxial crystal rectifier 31 has the crystal element electrically connected to an electrically conducting case 32 and the cat whisker electrically connected to a pin 33 which is electrically insulated from the Case 32. i A dummy crystal 34 has a body portion 35 externally. identical to the crystal rectifier case 32 and an extension 36 of smaller cross section which has an opening 37 in its end adapted to receive the pin 33. The end of the extension 36 is slotted as indicated by the numeral 38 to provide a spring loading on the pin. When assembled by sliding the pin 33 into the hole 37 in the extension 36 the crystal rectifier and the dummy crystal have the appearance of the microwave component 29 of Fig. 3. It will be apparent that the invention is not limited to the support of crystal rectifiers, but that other microwave components such as bolometers or thermistors may be supportedin a like manner.

A cap means 40 is mounted to the boss 15. The cap means includes a shell 41 having an internally threaded portion 42 which is attached to an externally threaded portion 43 of the boss 15. A chuck 44 is movably attached to the shell 41 by a rivet 45 and the chuck 44 is urged away from the end of the cap means 40 by a coil spring 46 which is loaded in compression. A recess 48 is provided in the end of the chuck 44 opposite the rivet 45 and the walls of the chuck around the recess are slotted to provide a spring or collet type of clamping action on bodies which are inserted into the recess 48.

The recesses 28 and 48 are identical in size and shape, and the bosses 14 and 15, the conductor termination 19 and the cap means 40 aredimensioned so that the bottoms of the two recesses are equidistant from the centerline of the waveguide when the microwave component 29 is in the mounted position. Since the ends of the microwave component 29 are identical in size and shape, it will be seen that it may be inserted in the supporting recesses 28, 48 in either of two orientations and still have the same portion of the microwave component between the openings 13, 13 and in the path of electromagnetic energy moving along the inside of the waveguide.

When the microwave component of Fig. 4 is being used the jack 23 may be electrically connected to the cat whisker of the crystal rectifier 31 via the support block 24, the dummy crystal 34 and the pin 33, or it may be electrically connected to the crystal element via the support block 24 3 and the case '32 depending upon the orientation of the microwave component 29. For one orientation the jack will be positive with respect to the case 20, for the other it will be negative.

The threaded portion'43 of the boss 15 andthe threaded portion 22 of the boss 14 are identical in size and sha e. Hence the cap means 40 and the conductor-termination 19 may be attached to either boss 14 or 15 without afiecting the position of the microwave component 29 with respect to the waveguide 11. A microwave component mount embodying the features of this invention will "have four possible modes of operation which may be selected and changed at will. An electrical connection may be made to either of two opposing sides of the waveguide and an output either positive or negative with respect to the waveguide wall may be obtained at either side.

The diametersof the openings 16, 17 are made greater than the outside diameter of the-microwave component 29 so that there will be no direct current path between :the microwave component and the mount other :than attthe block 24 and the chuck 44. In order to provideasuitable transmission path for microwave energy across the gaps between the microwave component and the openings 16, 17, grooves 50, 51 may be provided in the inner surfaces of the bosses 14, 15 to form a quarter-wave choke operative to prevent leakage of microwave energy into the space between the inner surfaces of the bosses 14, 15 and the microwave component 29. I

Another microwave component which may be mounted following the teachings of the invention is shown in Fig. 5. A bolometer 55 having the form of a INZI has a base 56 and a tip 57. A dummy unit '58 :having 'an' identical base 59 and the same general shape as the bolometer is provided with an extension 60 similar to the.

extension 36 of the dummy crystal 34 of Fig. 4. The -extension 60 has an opening in its'end forinsertiontof'ithe tip 57 and the walls are slotted to provide spn'ngxpressure on the tip. This assembly may be mounted in the support ing recesses 28 and 48 of Fig. 3 in the same manner that the microwave component 29 is mounted.

The mount described above may be constructed 'in'other fashions without departing from the teachings of the invention. For example, the bosses 14, 15, the portion of the waveguide located between the hoses, and the plug 18 may be made as a unitary housing having-anopening corresponding to openings 13, 13, 16, 17, and an opening in its side at a point 61. A length of Waveguide maybe mounted to the housing over the opening at point 61;

aise aaae v 4 i resulting in a structure electrically identical to that of Fig. 3.

Although several exemplary embodiments of the invention have been disclosed anddiscussed, it will be understood that other applications of the invention are possible and that the embodiments disclosed may be subjected to various changes, modificationsand substitutions without necessarily deparing from the spirit of the invention.

I claim' asmy' invention:

1. In a microwave component and mount therefor adapted to be connected .to a waveguide, the combination of a housing having an opening therein for electromagnetic coupling to said waveguide; a conductor termination connected to said housing, said termination having a first support means in a predetermined position relative to said opening; a cap removably connected to said housing, said cap having a second support means resiliently disposed relative thereto; a microwave component comprising an operative element and adummy element coupled together in ende'to-ntl relation, "said elements having identical mounting vstirfaties adapted to :be reversibly received by said first and secondrsupport means whereby said microwave component may be disposed within said housing by said first and second asuppo'rt'imeans, .said second support means resiliently urg ng said microwave component into ngagement with saidzfirst :snpport means, and said operative element being geometrically ymmetri al yip si ioned relative mlsaid p n n -ir pective of the orien ation o said.mocrawave.componentiinfsaid support means.

2. A combination ,asdefined-in claim 1,;in which s a id operativeelementiineludesra positive and a negativeterminal, said mountin surfacejof said-operativeelement comprising one of saig. terminals and being adaptedto electrically fionnect saidtqperative element .to one of said support means, andsaid .dummy. element including an electrical conductor electrically connecting the remaining of said terminals .to the .other of. said support means. i

7 References :Cited in ithe file of this :patent UNITED "STATES 'TPATENTS Re. 23,131 Webber June .28, 1949 2,159,782 Conklin .May 23, 1939 2,413,171 Qlitfordq .D ec.,24, 1946 2,441,598 Robertson... May s, 1 948 2,644,929 Kurnpf July ,7, v1953 2,662384 James let ill Dec. ,19, 119 53 2,673,;930 Matare Mar. 30, 1954' 2,700,749 Bird an. 25, 1955 2,7.48t273 Rustad 

